You may already be assuming this, but in looking at folders, I not only need to see a summary by sender, date and subject, but I need to be able to sort the folder summary by any of these three criteria. Each sort needs some special handling.

"Subject:" needs to handle occurences of "Re: " and "Fwd: " so that threads group toggether.

"From:" needs to handle addresses with and without angle brackets, since the same address may have multiple forms

"Date:", of course, need to handle different time zones.

It's also useful to be able to see if I've replied and/or forwarded the message.

The "out" or "sent" folder, of course, shows "To:" instead of "From:", so there is the added problem of sorting multiple recipient lists. I'd like to be able to see the same email summary header under each of the recipients, but only when I sort the summary based on "To:".